Note: This article relates to the free Allowed Products add-on.
Download the free plugin
Install and activate the plugin just as you would with any other WordPress plugin
Go to Affiliates → Settings → Integrations and enter the IDs of the products you want to allow commission for.
Note: By default, when this add-on is installed and activated, all products will be blocked from earning a commission. You will need to enter the IDs of the products you wish to allow commission for in order to allow affiliates to earn a commission on them (follow step 3 above to do this). This add-on is especially useful if you have a lot of products and only wish to allow commission to be earned on a few specific products.